A bicycle is a two-wheeled vehicle with pedals for propulsion. It is usually designed for riding on paved roads and paths. It is also used in racing and other competitive sports. Bicycles are relatively simple machines compared to motor vehicles and have many moving parts that can wear out. Regular maintenance and replacement of worn components is required to keep a bicycle in good working order. Some cyclists choose to do some of the work themselves, especially when they have a basic understanding of how their bike works.

There are many different types of bicycles. The type you choose should be based on your intended use, the terrain where you will ride, whether you will carry cargo or children, and your fitness level. Bicycles come in a wide range of prices, from low-cost utilitarian models to high-end racers.

The first practical bicycles were developed in the late 1860s. These were based on German inventor Karl Drais’s velocipede, which had a platform for the rider that was raised above the ground by cranks attached to the wheel. Drais’s design had one major flaw: it was difficult to maintain balance with the platform lowered below the seat.

To solve this problem, Englishman John Kemp Starley designed a bicycle with equal-sized wheels and a shorter platform in 1885. This design, which he called the safety bicycle, was a great success and led to the bicycle boom of the 1890s. During this time, cycling moved from being a sport and hobby to a form of basic transportation for people of all classes, races, and sexes.

Modern bicycles are designed to carry the rider comfortably while converting most of the energy from the rider’s movement into kinetic energy that moves the bicycle forward. To achieve this, the frame of a modern bicycle is constructed from lightweight materials, such as aluminum or steel. These materials are shaped to provide the frame with its strength, rigidity, and responsiveness. In addition, the seat is designed to allow the rider to sit in a comfortable upright position. Some seats even have longitudinal slots to avoid perineal pressure and saddle sores.

There are many things to consider when selecting a new bicycle, including your height, weight, and fitness level. To ensure a safe ride, it is important that your bicycle fit you properly. To check this, look for a frame size label on the bottom bracket and a measurement chart in the owner’s manual. These charts give you the reach and stack measurements of the frame, which should be close to your body measurements. You can also find other useful information in the owner’s manual, such as tips for riding safely and a list of recommended accessories. To reduce the risk of injury, it is essential that you use a helmet whenever you are riding your bicycle. You should also be familiar with local road rules and traffic laws.

Go is a programming language developed at Google. It is a general purpose imperative computer programming language with a syntax that is similar to C and the ability to run on all major operating systems. Go is designed to be easy to learn, with a minimal set of features intended to keep code concise and readable. Its features include a standard library, code package management, static typing, support for testing, and platform independence.

A satellite devoted to monitoring the Earth’s weather conditions is called a GOES (Geosynchronous Orbiting Environmental Satellite) satellite. The first GOES satellite was launched in 1974, and since then the system of geosynchronous equatorial orbiting weather satellites has become an essential element of U.S. meteorological operations. GOES satellites provide essential information for forecasting, tracking and monitoring hazardous weather conditions, such as thunderstorms, lightning, snowstorms, tornadoes, hurricanes and wildfires.

Each GOES satellite is equipped with two payload instruments, the GOES Imager and GOES Sounder. The Imager is a multichannel imaging instrument that provides real-time imagery of the Earth, while the Sounder is a 19-channel radiometer that senses emitted thermal energy and reflected solar energy to calculate vertical atmospheric temperature and moisture profiles. In addition, the GOES Sounder also monitors ozone and nitrous oxide.

The GOES 2nd generation series, GOES-R and GOES-T, are equipped with an Advanced Baseline Imager (ABI), which provides three times more spectral channels and five times faster scanning than the previous Imager. ABI is augmented by the Space Environment Monitor (SEM), which senses the near-Earth solar-terrestrial electromagnetic environment and transmits real-time data to NOAA National Weather Service offices and Volcanic Ash Advisory Centers. SEM is equipped with an Energy Particle Sensor (EPS), High Energy Proton and Alpha Particle Detector (HEPAD) and magnetometer.

Besides monitoring storms and fires, the satellites track temperature fronts, estimate precipitation during thunderstorms and hurricanes for flash flood warnings and snowfall accumulation for winter storm and snow melt advisories. The satellites’ sensors also map ice fields and observe the movement of sea and lake ice.

Because a GOES satellite stays above a fixed point on the Earth, it can continually watch for atmospheric “triggers” that can lead to severe weather conditions, such as the formation of thunderstorms, tropical cyclones, tornadoes and fires. The satellites also provide images of the Earth at night and in inclement weather, and monitor conditions such as ocean surface winds and arctic air mass patterns.

The National Oceanic and Atmospheric Administration (NOAA) oversees the development and operation of the GOES satellite system, while the National Aeronautics and Space Administration manages the procurement, design and manufacture of the spacecraft and its instruments, and launches the satellites into orbit. After completing an on-orbit checkout, NOAA assumes responsibility for the satellites. The GOES satellites are monitored and controlled by NOAA’s Satellite Operations Control Center in Suitland, Maryland. The GOES-3 and -4 satellites have an expected lifespan of three years, while the -5, -6 and -7 satellites are designed to operate for five years and will carry enough fuel to continue operating beyond that time, should the need arise.